Fourth Quarter & Full Year 2022 Earnings Presentation March 28, 2023

Disclaimer This presentation (“Presentation”) is for informational purposes only. This Presentation shall not constitute an offer to sell, or the solicitation of an offer to buy, any securities, nor shall there be any sale of securities in any states or jurisdictions in which such offer, solicitation or sale would be unlawful. No representations or warranties, express or implied, are given in, or in respect of, this Presentation. To the fullest extent permitted by law in no circumstances will Danimer Scientific, Inc. (the “Company”) or any of its subsidiaries, stockholders, affiliates, representatives, directors, officers, employees, advisers, or agents be responsible or liable for a direct, indirect, or consequential loss or loss of profit arising from the use of this Presentation, its contents, its omissions, reliance on the information contained within it, or on opinions communicated in relation thereto or otherwise arising in connection therewith. Industry and market data used in this Presentation have been obtained from third-party industry publications and sources as well as from research reports prepared for other purposes. The Company has not independently verified the data obtained from these sources and cannot assure you of the data’s accuracy or completeness. This data is subject to change. In addition, this Presentation does not purport to be all-inclusive or to contain all of the information that may be required to make a full analysis of investigations as an investor may deem necessary. FORWARD-LOOKING STATEMENTS Please note that in this Presentation, we may use words such as “appears,” “anticipates,” “believes,” “plans,” “expects,” “intends,” “future,” and similar expressions which constitute forward-looking statements within the meaning of the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements include, without limitation, statements regarding our expectations for full year 2022 capital expenditures and Adjusted EBITDA. Forward-looking statements are made based on management’s expectations and beliefs concerning future events impacting the Company and therefore involve a number of risks and uncertainties. The Company cautions that forward-looking statements are not guarantees and that actual results could differ materially from those expressed or implied in the forward-looking statements. Potential risks and uncertainties that could cause the actual results of operations or financial condition of the Company to differ materially from those expressed or implied by forward-looking statements in this Presentation include, but are not limited to, the overall level of consumer demand on its products; general economic conditions and other factors affecting consumer confidence, preferences, and behavior; disruption and volatility in the global currency, capital, and credit markets; the financial strength of the Company's customers; the Company's ability to implement its business strategy, including, but not limited to, its ability to expand its production facilities and plants to meet customer demand for its products and the timing thereof; risks relating to the uncertainty of the projected financial information with respect to the Company; the ability of the Company to execute and integrate acquisitions; changes in governmental regulation, legislation or public opinion relating to its products; the Company’s exposure to product liability or product warranty claims and other loss contingencies; disruptions and other impacts to the Company’s business, as a result of the COVID-19 global pandemic and government actions and restrictive measures implemented in response; stability of the Company’s manufacturing facilities and suppliers, as well as consumer demand for its products, in light of disease epidemics and health-related concerns such as the COVID-19 global pandemic; the impact on our business, operations and financial results from the ongoing conflict in Ukraine; the impact that global climate change trends may have on the Company and its suppliers and customers; the Company's ability to protect patents, trademarks and other intellectual property rights; any breaches of, or interruptions in, its information systems; the ability of its information technology systems or information security systems to operate effectively, including as a result of security breaches, viruses, hackers, malware, natural disasters, vendor business interruptions or other causes; its ability to properly maintain, protect, repair or upgrade its information technology systems or information security systems, or problems with its transitioning to upgraded or replacement systems; the impact of adverse publicity about the Company and/or its brands, including without limitation, through social media or in connection with brand damaging events and/or public perception; fluctuations in the price, availability and quality of raw materials and contracted products as well as foreign currency fluctuations; its ability to utilize potential net operating loss carryforwards; and changes in tax laws and liabilities, tariffs, legal, regulatory, political and economic risks. More information on potential factors that could affect the Company's financial results is included from time to time in the Company's public reports filed with the Securities and Exchange Commission, including the Company's Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, and Current Reports on Form 8-K. All forward-looking statements included in this Presentation are based upon information available to the Company as of the date of this Presentation and speak only as of the date hereof. The Company assumes no obligation to update any forward-looking statements to reflect events or circumstances after the date of this presentation. USE OF PROJECTIONS This Presentation contains projected financial information with respect to the Company. Such projected financial information constitutes forward-looking information and is for illustrative purposes only and should not be relied upon as necessarily being indicative of future results. The assumptions and estimates underlying such financial information are inherently uncertain and are subject to a wide variety of significant business, economic, competitive, and other risks and uncertainties. See “Forward-Looking Statements” above. Actual results may differ materially from the results contemplated by the financial forecast information contained in this Presentation, and the inclusion of such information in this Presentation should not be regarded as a representation by any person that the results reflected in such forecasts will be achieved. FINANCIAL INFORMATION; NON-GAAP FINANCIAL MEASURES Some of the financial information and data contained in this Presentation, such as Adjusted EBITDA, Adjusted EBITDAR and Adjusted Gross Profit has not been prepared in accordance with United States generally accepted accounting principles (“GAAP”). The Company believes these non-GAAP measures of financial results provide useful information to management and investors regarding certain financial and business trends relating to the Company’s financial condition and results of operations. The Company’s management uses these non-GAAP measures for trend analyses and for budgeting and planning purposes. A reconciliation of these non-GAAP financial measures to the closest GAAP measure is included in the Appendix to the Presentation. You should review the Company’s audited financial statements prepared in accordance with GAAP, which are included in its Annual Report on Form 10-K filed with the SEC. Forward-looking non-GAAP financial measures are presented without reconciliations to GAAP measures because the GAAP financial measures are not accessible on a forward-looking basis, and reconciling information is not available without unreasonable effort due to the inherent difficulty in forecasting and quantifying certain amounts that are necessary for such reconciliations. For the same reasons, the Company is unable to address the probable significance of the unavailable information, which could be material to future results. TRADEMARKS This Presentation contained trademarks, service marks, trade names, and copyrights of, the Company, and other companies, which are the property of their respective owners. The information contained herein is as of March 28, 2023, and does not reflect any subsequent events.

Danimer Investment Highlights Kentucky Plant Serves Near-Term Demand 1 2 3 4 5 6 PHA-Based Resins are Superior and Disruptive Sustainability Mandate Drives Permanent Adoption Short, Medium & Long-Term Strategic Finance Initiatives Ongoing Opportunity for Margin Expansion World-Class Teams and a Powerful Culture Our PHA-based resins are unique in the market as fully biodegradable in-home compost, natural soil and marine environments These highly-engineered materials can seamlessly replace petroleum-based plastics in most end-use categories Our products perform well on standard manufacturing equipment Our customers invest in long-term solutions, including through funded R&D partnerships A switch to PHA-based resin requires significant customer commitment Use of biodegradable materials provides a brand benefit and increasingly is a regulatory mandate Term loan strengthens liquidity position and ensures runway to positive EBITDA Part 2 Application for low-rate DoE loan to fund Greenfield facility now submitted Large market opportunity for DCT’s capital-light, low-cost process for PHA and bio-based acrylic acid attracting top-tier partner interest Stronger capacity utilization drives contribution margin at Kentucky plant Bainbridge greenfield plant design more efficient; drives scale benefits with ~$400mm of new capacity Danimer Catalytic Technology’s (DCT) high-margin processes, growth into scalable new markets, new partnerships, and technology licensing opportunities A deeply capable executive team with cadre of Danimer veterans and strong new leaders Ground-breaking engineering, leading research & development, and a deeply capable technical sales staff The driven Danimer culture reflects a deep commitment to help solve the global problem of environmental pollution All manufacturing processes and equipment commissioned and performing at or above currently expected through-put as of Feb 2023 Nameplate capacity of ~32.5 mm LBs of neat PHA supports ~65 mm LBs of finished resin At full capacity utilization and current market pricing and mix, expect ~$190 mm revenue and a very strong contribution margin

Kentucky Manufacturing – Process & Capability¹ Downstream Processing Unique Engineering Expertise Five Independent Vessels Fermentation High-Volume Extrusion Lines Blending, Pelletization & Extrusion Blending & Extrusion Engineered Materials Science Bacterial Production of PHA Proprietary Biotechnology ¹32.5 mm LBS of Neat PHA = 65 mm LBS Formulated PHA-Based Resin = ~$190 mm Revenue Three Independent Trains Filtering & Drying PHA FERMENTATION BROTH NEAT PHA FORMULATED PHA-BASED RESINS ¹ Intended to illustrate maximum potential at full utilization of design capacity; assumes pricing of $3 per lb.

Recent Customer Highlights Launched a new customer making specialty plastic containers for consumable dry-goods Zespri announced, through HAVI, plans for PHA-based cutlery in its snack business PHA-based cutlery launch planned with an additional customer for mid-year. Excited to work closer with HAVI – demand from several of their clients validated by strong initial trial performance across multiple end-use categories US Foods has launched Nodax-based straws under their “Evolve” brand Nodax-based straws now in all North American Starbucks locations, a growing number of Dunkin Donuts stores, food service in Sams Club and Costco, and increasingly available at retail, including CVS, Target, Safeway, Walmart and many other retailers. Mars-Wrigley expected mid-year launch for Skittles packaging, now evaluating wider use Single use coffee pods in development with multiple partners, a 550 mm LB annual European market opportunity for 2026 if proposed legislation is adopted in late 2024.* *Source: https://environment.ec.europa.eu/publications/proposal-packaging-and-packaging-waste_en

Q4 and Full Year 2022 Financial Summary Sales reflects $7.3 mm of growth in PHA-related sales more than offset by $9.9 mm of lower PLA-related sales, including $9.1 mm due to the Ukraine conflict, and service revenues of $4.8 mm compared to $8.0 mm in fiscal 2021 as customers move to commercialization. Adj. GP primarily reflects increased unabsorbed costs of capacity expansion in Kentucky. SG&A increase reflects higher administrative costs and headcount to support expected growth R&D costs include full-year of Novomer acquisition, closed August 2021 Full Year Comments Financial Summary Note:. Totals may not foot due to rounding.

Financial Outlook Adjusted EBITDA Expect 2023E Baseline Capex of $26 million to $31 million, excluding any DoE loan proceeds

Appendix

EBITDA Reconciliation Note: Totals may not foot due to rounding.

Adjusted Gross Profit Reconciliation Note: Totals may not foot due to rounding.